A Lean‐Zinc and Zincophilic Anode for Highly Reversible Zinc Metal Batteries
Chao Li, Qingguo Shao, Kan Luo, Yiqiu Gao, Wenwen Zhao, Ning Cao, Shiyu Du, Xin Jin, Peichao Zou, Xiaobei Zang
Abstract
Abstract Lean‐zinc anode is a promising configuration that can eliminate the trade‐off of energy density and cycle lifetime of zinc metal (Zn 0 ) batteries. However, there are rare investigations of lean‐Zn anode designs and it remains a grand change to sustain high zinc reversibility under lean zinc conditions. Herein, a lean‐Zn anode design based on a hierarchical and zincophilic cobalt metal (Co 0 ) nanowire‐decorated carbon host, which is derived from a ZnCo bimetallic organic framework, is reported. Within the lean‐Zn anode, the trace amount of Zn 0 acts as a zinc reservoir to make up for any irreversible loss of zinc source upon cycling, while the zincophilic Co 0 nanowires can guide uniform zinc nucleation and growth through a lattice matching mechanism. Consequently, high Zn 0 reversibility (average Coulomb efficiency of 99.6% for 4250 cycles), low nucleation overpotential (50.8 mV at 1 mA cm −2 ), and uniform and compact zinc electrodeposition are realized. When coupling the lean‐Zn anode with a Zn‐containing cathode, the full cell delivers high Coulomb efficiency (99.6% for 4250 cycles on average) and a long lifetime of more than 5000 cycles.